Cake Displays

hi just wondering what you girls do for cake displays at fairs n shows n things, I,m booked in to a few and was going to use one I had made 2 weeks ago now but have just had a look at it n it seems to have air pockets now n the fondant has gone funny I have kept cakes for a few days before n this has never happened? Do you,s use foam dummies under ur display cakes? As I was hoping to get a few fairs out of it before tossing. Thanks